1. [ noun ] (botany) any of several Old World coarse prickly-leaved shrubs and subshrubs having milky juice and yellow flowers; widely naturalized; often noxious weeds in cultivated soil
Synonyms: sow_thistle
Related terms: shrub milkweed Sonchus
2. [ noun ] (botany) tall Old World biennial thistle with large clasping white-blotched leaves and purple flower heads; naturalized in California and South America
Synonyms: Our_Lady's_mild_thistle holy_thistle blessed_thistle Silybum_marianum lady's_thistle
Related terms: herb Silybum
Similar spelling:   milk-white